Landlord - Tenant Law

What are the laws regarding a landlord giving a copy of a rental agreement to a tenant? Is this mandated by civil procedure where the landlord is required to deliver a copy or is it up to the tenant to obtain same? Also, would you happen to know the best place to go to online to research specific civil codes (easy to research please!) for Madera County, California or are all counties in California governed by the same Landlord-tenant laws? Any help is much appreciated, as my financially strapped sister with two young children is being severly harrassed, threatened and verbally abused by her landlord.

I'm not from California, but if it is harrassment it doesn't matter if it is the landlord or a stranger. It is illegal.